Fuze initiator

ABSTRACT

A fuze initiator is disclosed for initiating a fuze based upon the principle that an initiating force can be transmitted to a gripping element which will respond to the force similarly to a human hand reaction. The initiator includes biased open individual gripping members mounted for slidable movement in a divergent bore portion of a housing. The gripping members close about a fuze engagement shaft in response to movement of the gripping members from the divergent portion to a straight bore portion.

United States Patent [56] References Cited UNITED STATES PATENTS 2,992,594 7/1961 Anderson et al 89/1.5 D 3,171,666 3/1965 Benjamin et al. 287/103 X 3,181,908 5/1965 Clark 89/1.5 X 3,435,725 4/1969 Miller 89/1.5

Primary Examiner-Samuel W. Engle Attorneys-Charles M. Hogan and Eugene C. Goodale ABSTRACT: A fuze initiator is disclosed for initiating a fuze based upon the principle that an initiating force can be transmitted to a gripping element which will respond to the force similarly to a human hand reaction. The initiator includes biased open individual gripping members mounted for slidable movement in a divergent bore portion of a housing. The

gripping members close about a fuze engagement shaft in response to movement of the gripping members from the divergent portion to a straight bore portion.

I The present invention relates. to initiators and more particularly to a fuze initiator assembly to allow arming of projectiles, missiles, bombs and the like as released, for example, from aircraft.

- Numerous techniques and apparatus have been used to provide fuze initiation for dropped bombs, however, previous initiatorsin existence are very complicated in structure. As an example, known initiators may consist of assemblies comprising '15 or more component parts. initiators of this type are inherently difficult to assemble, more costly and have limited utility, in other words, are only of the single use type.

Accordingly, the present invention moves substantially beyond the prior'art and provides a simpler and safer assembly permitting an extensive reduction in size and weight while eliminating assembly and dimensional control problems resulting in a more emcient and compact structure. An object of the present invention is to provide a substantially improved fuze initiating assembly having fewer component parts.

.Another object is to provide a fuze initiator which contains no parts which can be lost during handling and loading.

A further object is to provide a fuze initiator which is resettable.

' SUMMARY OF THE INVENTION,

The {present invention provides an improvedfuze initiator assembly which, when activated, enables the arming sequence to commence. The initiator is of simple and economical construction and is resettable. Other details and advantages of this invention will become apparent as the following description of an exemplary embodiment thereof presented in theaccompanying drawings proceeds. I t

BRIEF DESCRIPTION OF THE DRAWINGS DESCRIIFT ION OF THE ILLUSTRATED EMBODIMENT Reference is now made to the drawings which illustrate an exemplary embodiment of the improved fuze initiator assembly of this invention, which is designated generally by the reference numeral 10. The fuze initiator is comprised of a housing 12 which is installed in a suitable environment such as a tail fuze well until it seats against a surface 14. Extending axially throughthe housing 12 is a stepped bore 16 which has a divergent bore portion 18 formed at one end of thehousing 12. An "-ring provides a sealing engagement between housing I2 and the surface 14.

The component part of the initiator 10 which enhances the uniqueness of the initiator is the collet shown generally as 20. The collet 20 has a main body portion 21 mounted forslidable movement in a bore 16. Extending from one end of body portion 21 are a plurality of fingers or gripping members 22 which are spring loaded or biased open to assume the configuration of the divergent inner wall 18 of the housing 12. At the extreme outer end of each of the fingers or gripping members 22 is a claw or detent member 24. The collet 20 responds similarly to the human hand in that when the initiator is assembled to the fuze, the fingers or gripping members 22 of the col-,

mated to the fuze, the fuze engagement shaft 26 forces the collet 20 farther into thehousing 12 along the bore 16 to a second position as seen in FIG. 3. During this assembly, as

seen in FIG. 3, the collet gripping members 22 grasp or close behind the lip or detent receiving portion of the engagement shaft 26 because of the change in geometry of the bore as the collet is urged to the second position.

An adapter shaft 28 is attached to collet20 by any suitable means such as threadableengagement therewith and extends through the bore 16' to the exterior of.the housing 12. An initiator lanyard 30 is attached to the adapter shaft 28. The adapter shaft 28 provides the link between the lanyard 30 and the collet 20. During the process of releasing the weapon from the aircraft, the lanyard 30 is pulled This force is transmitted through the adapter shaft 28 to thecollet 20. The resulting output function is that the fuze engagement shaft 26 is pulled enabling the fuze arming. sequence to commence. The portion of the adapter shaft 28 extending outwardlyof the housing 12 is of a greater dimension than the-bore 16 which limits the amount of axial movement of the; adapter shaft in one direction.

A reset compression spring 32 is mounted in bore 16 to act against collet 20 and serves two functions. The spring 32 insures that the collet 20 is maintained in the desired first position prior to initiator assembly to 'afuze. Consequently, the lip of the fuze engagement shaft can always be positioned beyond the detents of the collet gripping members before these members are closed. Secondly, when and if the fuze is required to be disassembled from the initiator, the compression spring 32 insures that the collet 20 will. return to the first position,- thereby allowing the fingersto open and releasing the engagement shaft: t

In some instances, a fuze requiresan electrical interfacing between the fuze andapparatus in other portions of the bomb.

Electrical contact rings-34 and 36 and lead-wires 38 and 40 provide this interfacing. As an example, a bomb may be inlet clasp a fuse engagement shaft 26. This completes the link between the fuze engagement shaft and an adapter shaft.

' As shown in FIG. I, the gripping members 22 of the collet 20 are in a relaxed or first position. When the initiator is tended for a tail fuze detonation and yet incorporatesa proximity fuze in the nose well. The fuze initiatorestablish'es the electrical circuit between the nose proximity fuze and the electrical detonator which is located in the'tail fuze. Because of the simplicity of, the design, the electrical components required for'this interfacing can be mounted into the housing as an integral part of thehousing assembly as illustrated herein. It is to be noted, however, that when no electrical circuitry is required, the initiator may be assembled without the electrical interfacing.

In operation, the bomb would be assembled by first installing the initiator 10 into the tail fuze well until it seats against a surface 14. The fuze is next installed into the tail fuze well. During this installation, the fuze engagement shaft 26 positions the collet 20 into thehousing 12 until the detents of gripping members 22 close behind the engagement shaft lip. The initiator and fuze engagement shaft remain in this second position until the bomb is released from the aircraft. Upon release, the lanyard pull is transmitted through the initiator and the engagement shaft is pulled, allowing the arming sequenceto begin.

It is seen that the fuze initiator disclosed herein has the added advantage that is'absent in'the prior art in that the present initiator is resettable. It is possible to pull the lanyard before the initiator is assembled to the fuze without destroying its operationalcapability. The result is that an initiator hasa collet for engaging a fuze engagement shaft, said collet being mounted in the divergent bore portion of said housing for slidable movement along the bore;

an adapter shaft attachable to said collet and extending through the bore and outwardly of the other end of the housing; and

means attached to said adapter shaft wherein when the projectile is launched the force is transferred from said means through the adapter shaft to the collet whereby a fuze engagement shaft is pulled allowing the arming sequence to begin.

2. An initiator as set forth in claim 1 in which said collet comprises a body portion slidable in said bore and gripping members extending outward into the divergent bore portion, said gripping members being biased outwardly to conform to the divergent bore portion to provide for insertion of a fuze engagement shaft therein; and

means for urging said collet axially in said bore so that the gripping members are in the divergent bore portion.

3. An initiator as set forth in claim 2 further comprising a detent element at the outer end of each gripping member to engage a lip of the engagement shaft upon insertion of the engagement shah into the divergent bore portion; and

in which the means for urging said collet comprises a compression spring mounted and acting against one end of said collet.

4. A fuze initiator assembly for engaging a fuze engagement shaft for projectiles, missiles, bombs and the like comprising:

a housing having a bore therethrough, said housing formed at one end to provide a divergent bore portion at one end of the bore;

a collet mounted for slidable movement in the bore adjacent the divergent portion end for engaging a fuze engagement shaft;

an adapter shaft attachable to said collet and extending through said bore and beyond the other end of the housmg;

means urging said collet to a first position for receiving the fuze engagement shaft;

said collet being moved to a second position upon insertion of the fuze engagement shaft into the initiator assembly wherein upon release of the projectile the resulting force is transmitted through the shaft and collet and the fuze engagement shaft is pulled allowing the arming sequence to begin.

5. An initiator assembly as set forth in claim 4 in which the collet comprises a main body portion slidable in the bore and gripping members extending axially from the body portion, said gripping members being spring loaded outward into the divergent portion of the bore when the collet is in the first position wherein the fuze engagement shaft can be inserted into the divergent bore portion and when the fuze engagement shaft moves said collet from the first position to the second position said gripping members close about the fuze engagement shaft because of movement of the gripping members from the divergent bore portion to the bore portion.

6. An initiator assembly as set forth in claim 5 in which said gripping members comprise a plurality of axially extending fingerlike elements; each of said fingerlike elements having a detent at the outer end thereof for cooperative engagement with a corresponding detent receiving portion on the fuze engagement shaft to prevent removal of the fuze engagement shaft when said collet is in the second position; and

a compression spring mounted in said bore urging said collet into the first position,

7. An initiator as set forth in claim 6 further comprising:

four gripping members extending axially outward from the collet main body portion; and

an initiator lanyard attachable to said adapter shaft. 

1. A fuze initiator assembly for projectiles, missiles, bombs and the like comprising: a housing having a bore therethrough, said housing having one end formed to provide a divergent bore portion; a collet for engaging a fuze engagement shaft, said collet being mounted in the divergent bore portion of said housing for slidable movement along the bore; an adapter shaft attachable to said collet and extending through the bore and outwardly of the other end of the housing; and means attached to said adapter shaft wherein when the projectile is launched the force is transferred from said means through the adapter shaft to the collet whereby a fuze engagement shaft is pulled allowing the arming sequence to begin.
 2. An initiator as set forth in claim 1 in which said collet comprises a body portion slidable in said bore and gripping members extending outward into the divergent bore portion, said gripping members being biased outwardly to conform to the divergent bore portion to provide for insertion of a fuze engagement shaft therein; and means for urging said collet axially in said bore so that the gripping members are in the divergent bore portion.
 3. An initiator as set forth in claim 2 further comprising a detent element at the outer end of each gripping member to engage a lip of the engagement shaft upon insertion of the engagement shaft into the divergent bore portion; and in which the means for urging said collet comprises a compression spring mounted and acting against one end of said collet.
 4. A fuze initiator assembly for engaging a fuze engagement shaft for projectiles, missiles, bombs and the like comprising: a housing having a bore therethrough, said housing formed at one end to provide a divergent bore portion at one end of the bore; a collet mounted for slidable movement in the bore adjacent the divergent portion end for engaging a fuze engagement shaft; an adapter shaft attachable to said collet and extending through said bore and beyond the other end of the housing; means urging said collet to a first position for receiving the fuze engagement shaft; said collet being moved to a second position upon insertion of the fuze engagement shaft into the initiator assembly wherein upon release of the projectile the resulting force is transmitted through the shaft and collet and the fuze engagement shaft is pulled allowing the arming sequence to begin.
 5. An initiator assembly as set forth in claim 4 in which the collet comprises a main body portion slidable in the bore and gripping members extending axially from the body portion, said gripping members being spring loaded outward into the divergent portion of the bore when the collet is in the first position wherein the fuze engagement shaft can be inserted into the divergent bore portion and when the fuze engagement shaft moves said collet from the first position to the second position said gripping members close about the fuze engagement shaft because of movement of the gripping members from the divergent bore portion to the bore portion.
 6. An initiator assembly as set forth in claim 5 in which said gripping members comprise a plurality of axiAlly extending fingerlike elements; each of said fingerlike elements having a detent at the outer end thereof for cooperative engagement with a corresponding detent receiving portion on the fuze engagement shaft to prevent removal of the fuze engagement shaft when said collet is in the second position; and a compression spring mounted in said bore urging said collet into the first position.
 7. An initiator as set forth in claim 6 further comprising: four gripping members extending axially outward from the collet main body portion; and an initiator lanyard attachable to said adapter shaft. 